Heatilator • GDST4336I, GDFL4136I, GDCR4136I, GDCL4136I • 2129-900 Rev. W • 12/15
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General Rules:
• A maximum of three 90° elbows (or six 45° elbows) may
be used in any vent con
fi
guration. Some elbows may be
installed horizontally. See Figure 7.6.
• Elbows may be placed back to back anywhere in the
system as long as the
fi
rst 90° elbow is a starter elbow
except as shown in Figure 7.3.
• When penetrating a combustible wall, a wall shield
fi
restop must be installed.
• When penetrating a combustible ceiling, a ceiling
fi
restop
must be installed.
• Horizontal runs of vent do not require vertical rise;
horizontal runs may be level.
• Horizontal termination cap should have a 1/4 inch
downward slant to allow any moisture in cap to be
released. See Figure 7.3.
E. Vent Diagrams
Top Vent—Horizontal Termination—Two 45° Elbows
Installation requirements to replace the
fi
rst 90° elbow with two 45° elbows:
4 ft min.
(1.22 m)
16 ft max.
(4.87 m)
1/4 in. max.
(6 mm)
Figure 7.3
Note: The Multi-Sided series
fi
replaces can adapt
to SLP series vent pipe, if desired.
When venting off the top of the unit, attach a DVP-2SL adapter to
the appliance starting collar, immediately followed by a minimum
48 inch vertical section of SLP series vent pipe.
After
the 48 inch vertical section, the venting table rules
must be followed. The
fi
rst 48 inch vertical section is NOT
counted as part of the
vertical
components in the table. It is
still counted as part of the overall maximum run. All venting
table rules for the vent run must still be followed.
Example:
DVP pipe 3 ft. min. vertical = 11 ft. max. horizontal
SLP pipe 7 ft. min. vertical = 11 ft. max. horizontal
Note:
Reference Figure 7.14 for
special instructions for use of 45º
elbow on rear vent appliances.
